Polyurethane compositions

Abstract

Novel polyurethane compositions having excellent bond strength, thermal resistance and resistance to hot water are provided by a polymeric polyol and an organic polyisocyanate at a hydroxyl group/isocyanate group equivalent ratio (NCO/OH) of 1 to 10, wherein said polymeric polyol is a polyurethane polyol prepared from a polyester polyol and an organic diisocyanate, said polyurethane polyol having a number average molecular weight of 3,000 to 50,000, said polyester polyol being composed of the following structural unit -O-CH2-CH2-CH(CH3)-CH2-CH2-O-(I) the following dicarboxylic acid structural unit -CO-(CH2)n-CO-(II) wherein n is an integer from 1 to 12, and the following dicarboxylic acid structural unit -CO-Ar-CO-(III) wherein Ar is the divalent residue of an aromatic hydrocarbon of 6 to 10 carbon atoms, and the molar ratio of structural unit (II) to structural unit (III) being in the range from 1/5 to 5/1, and said polyester polyol having a number average molecular weight of 600 to 8,000.

What is claimed is: 
     
       1. Polyurethane compositions comprising a polymeric polyol (A) and an organic polyisocyanate (B) at a hydroxyl group/isocyanate group equivalent ratio (NCO/OH) of 1 to 10, wherein said polymeric polyol (A) is a polyurethane polyol prepared from a polyester polyol and an organic diisocyanate, said polyurethane polyol having a number average molecular weight of 3,000 to 50,000, said polyester polyol being composed of the following structureal unit   --O--CH.sub.2 --CH.sub.2 --CH(CH.sub.3)--CH.sub.2 --CH.sub.2 --O--(I)     the following dicarboxylic acid structural unit     --CO--(CH.sub.2).sub.n --CO--                              (II)     wherein n is a integer from 1 to 12, and the following dicarboxylic acid structural unit     --CO--Ar--CO--                                             (III)     wherein Ar is the divalent residue of an aromatic hydrocarbon of 6 to 10 carbon atoms, and the molar ratio of structural unit (II) to structural unit (III) being in the range from 1/5 to 5/1, and said polyester polyol having a number average molecular weight of 600 to 8,000.   
     
     
       2. The polyurethane compositions as defined in claim 1, wherein a compound having at least one hydroxyl group and at least one epoxy ring in the molecule (C) is further contained. 
     
     
       3. The polyurethane compositions as defined in claim 1 or 2, wherein said polymeric polyol (A) is a polyurethane polyol prepared from a polyester diol and an organic diisocyanate, said polyurethane polyol having a number average molecular weight of 3,000 to 50,000, said polyester diol being composed of the following structureal unit   --O--CH.sub.2 --CH.sub.2 --CH(CH.sub.3)--CH.sub.2 --CH.sub.2 --O--(I)     the following dicarboxylic acid structural unit     --CO--(CH.sub.2).sub.n --CO--                              (II)     wherein n is an integer from 1 to 12, and the following dicarboxylic acid structural unit     --CO--Ar--CO--                                             (III)     wherein Ar is the divalent residue of an aromatic hydrocarbon of 6 to 10 carbon atoms, and the molar ratio of structural unit (II) to structural unit (III) being in the range from 1/5 to 5/1, and said polyester polyol having a number average molecular weight of 1,500 to 2,200.   
     
     
       4. The polyurethane compositions as defined in any of claims 1 through 3, wherein said organic diisocyanate is composed mainly of isophorone diisocyanate or 2,4-tolylene diisocyanate. 
     
     
       5. The polyurethane compositions as defined in any of claims 1 through 4, wherein said structural unit (II) is the residue of sebacic acid or adipic acid. 
     
     
       6. The polyurethane compositions as defined in any of claims 1 through 5, wherein said structural unit (III) is the residue of terephthalic acid or isophtalic acid. 
     
     
       7. The polyurethane compositions as defined in any of claims 1 through 6, wherein the molar ratio of structural unit (II) to structural unit (III) is in the range from 1/2 to 2/1. 
     
     
       8. The polyurethane composition as defined in any of claims 1 to 7, wherein said compound (C) having at least one hydroxyl group and at least one epoxy ring in the molecule is a reaction product of a polyhydric phenol or polyhydric alcohol with a polyfunctional halohydrine or a reaction product thereof with a hydroxyl-containing compound. 
     
     
       9. The polyurethane compositions as defined in claim 8, wherein said polyhydric phenol is bisphenol A or tetrahydroxydiphenylethane. 
     
     
       10. The polyurethane compositions as defined in claim 8, wherein said polyhydric alcohol is glycerol or pentaerythritol. 
     
     
       11. The polyurethane compositions as defined in claim 8, wherein said polyfunctional halohydrine is epichlorohydrine. 
     
     
       12. Adhesive compositions comprising a polymeric polyol (A) and an organic polyisocyanate (B) at a hydroxyl group/isocyanate group equivalent ratio (NCO/OH) of 1 to 10, wherein said polymeric polyol (A) is a polyurethane polyol prepared from a polyester polyol and an organic diisocyanate, said polyurethane polyol having a number average molecular weight of 3,000 to 50,000, said polyester polyol being composed of the following structureal unit   --O--CH.sub.2 --CH.sub.2 --CH(CH.sub.3)--CH.sub.2 --CH.sub.2 --O--(I)     the following dicarboxylic acid structural unit     --CO--(CH.sub.2).sub.n --CO--                              (II)     wherein n is an integer from 1 to 12, and the following dicarboxylic acid structural unit     --CO--Ar--CO--                                             (III)     wherein Ar is the divalent residue of an aromatic hydrocarbon of 6 to 10 carbon atoms, and the molar ratio of structural unit (II) to structural unit (III) being in the range from 1/5 to 5/1, and said polyester polyol having a number average molecular weight of 600 to 8,000.   
     
     
       13. The adhesive compositions as defined in claim 12, wherein a compound having at least one hydroxyl group and at least one epoxy ring in the molecule (C) is further contained. 
     
     
       14. The adhesive compositions as defined in claim 12 or 13, wherein said organic diisocyanate is composed mainly of isophorone diisocyanate or 2,4-tolylene diisocyanate. 
     
     
       15. The adhesive compositions as defined in any of clims 12 through 14, wherein said structural unit (II) is the residue of sebacic acid or adipic acid. 
     
     
       16. The adhesive compositions as defined in any of claims 12 through 15, wherein said structural unit (III) is the residue of terephtalic acid or isophthalic acid. 
     
     
       17. The adhesive compositions as defined in any of claims 12 through 16, wherein said molar ratio of structural unit (II) to structural unit (III) is in range from 1/2 to 2/1.